How Your Brain Grows With You

Our brain is more "plastic," or impressionable, now than at any other time in life, Dr. Brizendine says. It's also growing fast: By your fifth birthday, your brain is 90 percent of its adult size! This is a great time to learn a second language; it builds an enhanced ability to concentrate that can last into adulthood and may even delay age-related dementia. Experts aren't yet sure why, but bilingual adults have denser gray matter in areas that help control language and communication, suggesting that learning multiple languages as a kid increases blood and oxygen flow to the brain and keeps nerve connections healthy.